Originally Posted by psneeld
I prefer telling guests to "push that button" when done
True, that's what I'd say. But what they'd hear is "just push the button, and it will all magically disappear."
That generally leads to a very unpleasant job for me the next day.
I'd much rather force them to think about it. It's even better if they find it difficult; maybe then they'll walk up the dock to use the public restroom in the marina.